Delamination Problem-Help Please

jpowers123 · Post by **jpowers123** » Sun May 30, 2010 8:18 am

Well, I finished my Prospector this February and was thriled with the end product, with one exception. I now have four or five spots where the fiberglass has bubbled/delaminated. I first notied it in small dime size spots that are now as much as 8 inches apart. This only occured on the outside of the hull. Any advice on how I fix this? Do I need to remove all of the fiberglass on the outer hull? I actually patched one spot when I first finished the hull and what I noticed was that the epoxy was not dry under the bubble. I believe it may have been from improperly mixed epoxy but that is just a guess. I had a buddy helping me that insisted it was good practice to mix and apply from the same cup. On the inside I instsied on mixing in one cup and pouring into another cup for application, so I suspect that may have been the problem, again, only a guess on my part and this is my first build so who knows. The bubbles appear to be filled with air so I am not sure if that info is of any help. Any assistance in how to repair these spots would be greatly appreciated, especially since canoe season is now upon us in Connecticut.

Post by **Patricks Dad** » Sun May 30, 2010 1:27 pm

first off... Mixing and applying in the same cup is fine. As long as everything you pump into the cup is well mixed. You need to ensure that you scrape the edges and bottom of the cup thoroughly when mixing. Pouring from a mix cup into an application cup won't change anything (my opinion). If there is unmixed epoxy in the mix cup, you'll just pour it into the application cup and have the same problem. There's no getting around the need to mix thoroughly.

If you have spots that need repairing, you could carefully cut them out and patch with a similarly shaped piece of glass and feather the epoxy out around the patch (be sure to sand an area larger than the patch so the new epoxy will adhere to the old epoxy). One technique I've seen is to lay a layer of celophane on top of the patched area and roll or squeege it to smooth out the patch. Remove the celophane when the epoxy cures.

If the bubbles are small and filled with air you might be able to simply inject epoxy into the bubbles to fill them up (1 small hole to inject the epoxy and another small hole for the air to escape.

Rod Tait · Post by **Rod Tait** » Mon May 31, 2010 7:50 pm

Are the spots growing in size? If they are, then I suspect epoxy that was not mixed either properly or in the proper ratio. The uncured epoxy may be heating up and expanding as temps rise. Do you think this may be the reason for growing spots? If so, then you will have to remove the areas and see how far it goes. I once had a canoe in my shop that someone had built, never finished, hung it in the rafters of his barn for over ten years. His wife offered to pay to have the canoe finished for their anniversary. After ten years, the epoxy was not cured and I had to cut out areas to find good stuff to bond to. Better to find this out now and fix it before it gets worse.

jpowers123 · Post by **jpowers123** » Mon May 31, 2010 9:07 pm

The spots have been growing in size. When I did the first repair the quarter sized spot turned into the about a 9 X 6 inch spot. It was as you say, the epoxy seemed to have not hardened at all in that spot. I fear this is the case. I suppose the best thing to do then is to cut out the bubbles and try to peel back the glass by hand until it stops and then faether in a patch? If it is fully cured the glass should be solidly attached, correct? Unfortunately I did varnish already so should I establish the patch sizes, mask it off, sand through to the wood in those spots, and repair? Any suggestions on the repair strategy? I did do the one spot and learned a few things but any advice helps.

Rod Tait · Post by **Rod Tait** » Tue Jun 01, 2010 11:38 am

Firstly, I would not simply tear out the patch You are likely to tear wood as well. Purchase a heat gun for stripping paint and then use that to remove the glass. In the areas that are not bonded, it will come off very easy with heat. If the bond is good, the glass with take some heat and effort to remove. Once you reach that point, stop, feather in the eges by sanding and then patch. If there is uncured eoxy, you will need to remove that with laquer. The problem is that you will not know if there are any other areas on the boat that may appear once you put the whole boat out in the sun for a day and let it heat up. If there are many and probably some that you don't know about, you might feel it better to do the whole thing over again, by stripping all the glass off with heat, re-sand then re-apply new glass. I have info on this process on my web site on the "How To" page

jpowers123 · Post by **jpowers123** » Tue Jun 01, 2010 7:04 pm

That is a great help. Thanks so much.

jpowers123 · Post by **jpowers123** » Tue Jun 01, 2010 7:09 pm

You know, I recently moved from San Diego CA to Connecticut and no longer have a nice indoor shop area. Will I be able to do the glass outdoors in the summer as long as I am able to keep it covered overhead and it will not get rained on?